Fathers Playing Catch With Sons By Donald Hall. North Point, 198 Pages, $13.95

``Essays on Sport (Mostly Baseball).`` ``Mostly`` ought to be darkly italicized, perhaps, but otherwise the subtitle is a fair description of what`s inside. Hall writes beautifully and vividly about sports, especially his beloved baseball, and at his best he brings to life that world, the one that tuned into games on the radio late at night:

``We listened on the dark screen porch, an island in the leaves and bushes, in the faint distant light from the street, while the baseball cricket droned against the real crickets of the yard. We listened while reading newspapers or washing up after dinner. We listened in bed when the Tigers were on the West Coast, just hearing the first innings, then sleeping into the game to wake with the dead gauze sound of the abandoned air straining and crackling beside the bed.``

Yet there`s a disturbing quality in the book, a tone struck even in the first paragraph of the introduction: ``Half of my poet-friends think I am insane to waste my time writing about sports and to loiter in the company of professional athletes. The other half would murder to take my place.`` What a peculiar way to write about sportswriting, I thought. And then, on second thought, what an even more peculiar way to write about one`s friends. This faintly hostile note grew stronger as I read along. Balanced against the unmistakable love Hall bears for baseball in general and for Boston in particular (Fenway Park, the Boston Garden, the Celtics) is a seething irritability not quite disguised by his jollity or glittering prose.

So basketball and football, according to Hall, ``encourage penis-envy prose.`` He writes, of Ivy League football: ``These teams executed plays the way blind men with Parkinson`s disease executed horses. On the whole, I enjoyed the game.`` Football stadium fans are involved in ``the hobby of violence--by which I mean not an idea of violence, please, but murder, rape, suicide, blood, broken bones showing splinters through the skin, entrails on the sidewalk. . . .`` I shudder to think where Hall is watching his football games.

He plays favorites without making distinctions. In the title essay, pitcher Dock Ellis is a gentle hero, teasing and encouraging the overweight, bearded, out-of-shape Hall, who has come to spend a week in training with the Pittsburgh Pirates. In the later essay, ``The Country of Baseball,`` Dock Ellis is still the hero, though there he`s deliberately hitting batters in the head, the kidneys, the side to boost his own team`s morale.

Hall is compulsively partisan: Baseball is better than basketball, basketball is better than hockey, hockey is better than football. (Hall hates football. ``Baseball is fathers and sons. Football is brothers beating each other up in the backyard, violent and superficial.``) He is an extremist, needing to exalt, to praise or to sneer at and mock. Like most us, he`s gentler poking fun at himself, but more often he`s on his feet yelling at some other poor soul, cheering, raging, keeping score, trying to act as if it`s all in fun, grinning between clenched teeth.

Hall explains his love of baseball this way: ``As the ripples in the sand (in the Kyoto garden) organize and formalize the dust which is dust, so the diamonds and rituals of baseball create an elegant, trivial, enchanted grid on which our suffering, shapeless, sinful day leans for the momentary grace of order.`` A fine, dazzling explanation of all forms of human play;

nonetheless, I suspect Hall`s real fascination with sports is that it lets him take sides.

This is not to undermine the real accomplishments of the book. Hall can be genuinely funny, especially about his week with the Pirates, describing for instance a case of mistaken identity between the bearded poet and one of the Pirate players: ``One day I wear Bob Johnson`s uniform. Two very old men, puzzled at my appearance, consult their programs. `Bob Johnson,` says one of them. `Two hundred and twenty-five pounds, six foot two.` (These statistics are rather close to my own. However, Johnson is not yet 30 and has arranged his body in a fashion more appropriate to an athlete.) The two old men are silent for a moment. Finally, one says, `It`s how that hair on the face can be so deceptive.```

He is tender and melancholy, writing of the tradition of the old-timers`

game: ``For symmetry and shape we require the crepuscular evening baseball of the old-timers` game, the children of 50 years ago, and the bright heroic 28- year-olds of our maturity, gather to celebrate in shadow the rituals of noon.`` True, there are some things one wishes Hall had left out: ``O Fenway Park,`` a dinky hats-off tribute Hall`s favorite stadium; a short essay on poetry w devotee could love; and two of Hall`s own middling-poor poems oke prose. For baseball lovers with special attachments to Boston, I`m sure it will seem heaven-sent.